Aircraft and engine manufacturers may be developing heating and cooling systems, which include heat exchangers installed within gas turbine engines for rejecting heat loads of the gas turbine or another system utilizing the gas turbine engine. For example, an aircraft may have a refrigeration system including heat exchangers installed within a fan bypass duct of a gas turbine engine, such that the airstream may pass through the heat exchangers in an axial direction of the engine. The heat exchangers create a blockage in the fan bypass duct and produce a pressure difference, thereby drawing air through the heat exchangers in the axial direction.
The typical system may include heat exchangers distributed substantially around the entire circumference of the fan bypass duct, which may therefore create blockage in the engine air stream resulting in a pressure drop and a subsequent decrease in engine thrust. To compensate for the decreased engine thrust, the system may increase the supply of fuel to the turbine. Furthermore, at somewhat low airflow rates, the blockage may not create a sufficient pressure difference across the heat exchangers thereby drawing less air through the heat exchangers and decreasing the cooling rate of the system. Conversely, at somewhat high airflow rates, the blockage may create somewhat large pressure drops or even possibly choke the engine stream flow.
Therefore, a need exists for an improved engine and process for efficiently rejecting heat from the heat exchangers within the engine while decreasing pressure losses.